Dispenser and fluid-driven proportioning pump

ABSTRACT

A fluid dispenser includes a diluent fluid inlet; a fluid-driven proportioning air pump in fluid communication with a diluent fluid inlet, the air pump being driven by fluid from the diluent fluid inlet and having an air outlet isolated from the diluent fluid inlet; a fluid container having first and second openings, the first opening in fluid communication with the pump air outlet; and wherein the pump creates air pressure and flow to evacuate the container of fluid through the second opening. An associated method of evacuating fluid from a container includes supplying a diluent fluid to the proportioning air pump through the pump fluid inlet; delivering a volume of air from the pump air outlet to the container in order to displace a similar volume of fluid and evacuate that volume of fluid from the container; and diluting the evacuated fluid with diluent fluid from the pump fluid outlet.

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to fluid dispensing systems and, more particularly, to a volumetric displacement-based dispenser.

BACKGROUND OF THE INVENTION

Dispensing of chemical product concentrates requiring dilution prior to use presents the problem of how to accurately draw a desired amount of concentrate from a container. The two most common types of dispensing systems used in this area are eductive dispensers and gravity feed dispensers, which eductive dispensers being the more prevalent of the two alternatives. Each of these types of dispensers suffers from inherent design deficiencies.

Eductive dispensing systems utilize a venturi device in order to draw chemical concentrate from a container connected to the system. Specifically, a venturi nozzle is connected with a supply of diluent fluid as well as to the chemical container. The flow of diluent fluid through the venturi nozzle creates a partial vacuum in the supply line connecting the chemical container to the venturi device. This partial vacuum draws concentrate from the container to the venturi device where it mixes with the diluent fluid as it passes through the spray nozzle.

Eductive systems suffer from two primary drawbacks. First, these systems do not prevent potential contamination of the chemical storage containers or the diluent fluid supply, which is commonly the facility water supply, with the water/chemical mixture when flow of the mixture is shut off at the venturi device. When the flow of water/chemical mixture is shut of at the venturi, pressure in the portion of the system below the eductor rises. If the pressure in this system reaches a level greater than the chemical inlet pressure at the venturi, or eductor, then it is possible for the water/chemical mixture to overcome the inlet pressure and flow back into the chemical supply line or the water supply line. The second issue with these systems is that require relatively high water pressure in the diluent fluid supply in order to produce consistent dispensing. However, in more isolated portions of the United States and in many foreign countries, the available water pressure falls far below the threshold needed for an eductive system to appropriate correctly.

The second type of system frequently used in this industry is a gravity feed system in which the chemical storage container is positioned above the diluent fluid supply. The container is opened and closed to allow a relatively accurate amount of chemical concentrate to fall into a collection chamber where it is diluted. While these gravity feed systems do prevent backflow issues and are able to effectively operate independently of the available water pressure, they introduce other problems. First, because these systems dispense concentrate by opening an orifice and allowing concentrate to flow from the container for a set period of time, they depend on a large number of difficult to control variables for accurate dispensing, including controlling the operation of the orifice and the flow rate of the concentrate, which may vary with factors such as ambient temperature and the amount of concentrate remaining in the container. Second, placing the chemical container in an upside-down position to enable concentrate to flow down and out of the container frequently results in leaks from the dispenser, thereby causing down time and additional expense in clean-up and maintenance.

Therefore, it would be advantageous to produce a dispenser capable of accurate dispensing that isolates the diluent fluid supply from the chemical concentrate supply and operates independently of the available diluent fluid pressure without positioning the chemical concentrate supply in an awkward upside-down position.

The present invention is directed to overcoming one or more of the problems set forth above.

SUMMARY OF THE INVENTION

An aspect of the present invention is to provide a dispensing system for concentrates that isolates the diluent fluid supply from the chemical supply and prevents backflow.

Another aspect of the invention is to provide a dispensing system for concentrates that operates independently of the available diluent fluid pressure.

Yet another aspect of the invention is to provide a dispensing system for concentrates that is compatible with “off-the-shelf” chemical containers and does not require that concentrates be packaged in proprietary containers.

Another aspect of the invention is to provide a dispensing system for concentrates that accurately dispenses a volume of chemical concentrate while minimizing leaking of concentrate.

In accordance with the above aspects of the invention, there is provided a fluid dispenser that includes a diluent fluid inlet; a fluid-driven proportioning air pump in fluid communication with a diluent fluid inlet, the air pump being driven by fluid from the diluent fluid inlet and having an air outlet isolated from the diluent fluid inlet; a fluid container having first and second openings, the first opening in fluid communication with the pump air outlet; and wherein the pump creates air pressure and flow to evacuate the container of fluid through the second opening.

In accordance with another aspect of the invention, there is provided a fluid dispenser for use with a fluid container that includes a diluent fluid inlet; a fluid-driven proportioning air pump in fluid communication with the diluent fluid inlet, the air pump being driven by fluid from the diluent fluid inlet and having an air outlet isolated from the diluent fluid inlet; a connection between the air outlet of the proportioning air pump and the fluid container including a generally vertical wall and a generally horizontal support surface connected to the vertical wall; at least one rail mounted to the wall at an angle relative to said support surface; a carriage slideably mounted to said rail; a docking cap mounting within said docking cap; and wherein the docking cap engages a neck of the fluid container as the container is slid across the support surface, resulting in the docking cap and the carriage sliding at a downward angle relative to the support surface along the rail and compressing the docking cap onto a top surface of the container.

In accordance with yet another aspect of the invention, there is provided a method of evacuating fluid from a fluid container that includes the steps of providing a fluid-driven proportioning air pump having a fluid inlet, a fluid outlet, and an air outlet; supplying a diluent fluid to the proportioning air pump through the fluid inlet of said air pump; delivering a volume of pressurized air from the air outlet of the air pump to the interior of the fluid container through a first opening in the container in order to displace a similar volume of fluid from the container and evacuate the volume of fluid from the container through a second opening in said container; and diluting the volume of fluid displaced from the container with diluent fluid from the fluid outlet of said air pump.

These aspects are merely illustrative of the various aspects associated with the present invention and should not be deemed as limiting in any manner. These and other aspects, features and advantages of the present invention will become apparent from the following detailed description when taken in conjunction with the referenced drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference is now made to the drawings which illustrate the best known mode of carrying out the invention and wherein the same reference numerals indicate the same or similar parts throughout the several views.

FIG. 1 is a front elevation view of a volumetric displacement-based dispenser according to an embodiment of the present invention with the cover on the dispenser.

FIG. 2 is a three-quarter view of the dispenser of FIG. 1.

FIG. 3 is a front partial section view of a container docking arrangement in an alternate embodiment.

FIG. 4 is a close-up side section view of the container docking arrangement of FIG. 3

FIG. 5 is a side section view of a diluent fluid metering and diverting arrangement in an alternate embodiment.

FIG. 6 is a rear view of the diverting portion of the arrangement of FIG. 5.

FIG. 7 is a side section view of a fluid-driven proportioning air pump in yet another embodiment of the dispenser.

FIG. 8 is close-up section view of the pump of FIG. 7.

FIG. 9 is a plan section view of the pump and dispenser of FIG. 7.

FIG. 10 is a side section view of the bottom end of the pump of FIG. 7.

FIG. 11 is a partial cutaway view of a dispenser, showing its container docking arrangement, metering and diverting arrangement, and proportioning air pump.

FIG. 12 is a front view of a dispenser according to another embodiment with the front cover of the dispenser removed.

DETAILED DESCRIPTION

In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. For example, well-known methods, procedures, and components have not been described in detail so as not to obscure the present invention.

FIGS. 1-12 illustrate a preferred embodiment of a dispenser and fluid-driven proportioning pump according to the present invention. In the disclosed embodiment, the dispenser offers a choice between two flow rates for the diluent fluid. However, those of skill in the art will recognize and appreciate that the present invention also encompasses dispensers offering a single flow rate or more than two alternative flow rates.

The unit is hung on the wall with two screws passing through eyeholes in the back of the base. A water pressure line is connected to the left side of the unit, but can also be connected to the right side of the unit by first switching the female hose (1) and cap fittings (2). In order to connect or “dock” the chemical bottle (3) to the unit, it is first slid through the opening in the right side of the unit. The neck of the bottle contacts the docking seal mounting (4) which is part of the spring loaded carriage assembly (5). This assembly slides along downwardly inclined rails (6) that are attached to the base (7). The spring loaded docking seal mounting moves downward until the elastomer docking seal (8) is compressed on top of the bottle insert (9). When the bottle comes to a stop (10), a hook (11) in the base engages the docking seal mounting to hold the bottle in the docked position against the force produced by springs (12, 13).

Docking the bottle also opens two spring loaded check valves mounted in the bottle insert: one check valve (14) is for air pressure in, and the other (15) is for chemical out. These check valves spring-load closed when the bottle is removed so that chemical will not leak out if the bottle is dropped or squeezed. A metering orifice (16) is located between the chemical port check valve and the tubing (17). Its purpose is to control the delivery of chemical from the bottle. The metering orifice may be sized to produce the desired chemical flow characteristics.

Once the unit is ready to dispense chemical, the knob (18) is turned to the left to select a first desired water flow rate or to the right to select a second, higher water flow rate. The knob spring returns to off in both cases when it is released. However, there is a detent in the knob and cover that keeps the know in the right hand position so that the water flow remains open for filling large containers. After filling, the operator then turns the knob to the left to overcome the detent so that the valve and knob can spring return to the neutral off position. Water is delivered when either one of the two knob projections (19) drives either button (20) downward, moving the magnet (21) downward until magnetic force lifts the spring (22) loaded plunger (23) inside the enclosing tube (24) off the central hole in the diaphragm (25), causing pressure to lift the diaphragm off its seat (26) and allow water to flow. Water flows through a screen (27), and then through a nozzle (28). The purpose of the screen is to narrow and straighten the water stream so that it is directed into the funnel (29). When the knob is released, the compression spring (30) returns the button back up against the knob projection and causes the knob to return to its vertical off position. Assisting this spring is an extension spring (31) that is attached to the knob and the cover (32). Because the knob is removed along with the cover of the unit, another purpose of this spring is to be sure the knob is always in the same vertical position, otherwise the knob projection (33) would not engage the hole (34) in the lever (35) when the cover and knob assembly is snapped onto the base.

When either water valve is activated, water enters the reciprocating pump (36). Depending on which set of two water piston ports (37, 38) are opened or closed by their port pistons (39, 40), the water piston (41), sealed with two elastomer u-cup seals (60, 61), either moves upward or downward. In this case, the assembly is shown with the spring (52) loaded upper pistons (39) opened to their ports, and the spring (53) loaded lower pistons (40) closed to their ports. Therefore the water piston moves upward from water pressure acting on the bottom of the water piston and expels water out of the chamber (55) and into the orifice (42) leading to the water valves (43). The water piston continues moving upward until the upper surface of the shaft (54) contacts chamber (55) surface. Pressure below the water piston causes the shaft to move downward against two spring (46) loaded rollers (47) until the peak (48) of the cammed surface (49) of the shaft is reached. Just as the shaft continues to move downward and the rollers have passed this peak, the shaft accelerates until the upper shaft shoulder (50) contacts the upper port piston mount surface (51) and snaps both upper pistons closed to their ports simultaneously as the lower pistons are spring loaded open to their ports. Water pressure now transfers from below the water piston to above it, causing the piston to move downward and expel water from the chamber (78) into the water valves. When the lower shaft shoulder (44) contacts the bottom surface of the water piston housing (45), the process reverses, moving the shaft upward until shaft shoulder (77) shifts the upper ports opened and the lower ports closed again. This repetitive reciprocating motion stops when either water valve is closed.

Attached to the reciprocating water piston shaft (56) is an air piston (57) sealed with an elastomer u-cup seal (58) that expels air pressure from the air pressure chamber (59) through an elastomer umbrella check valve (62) on the down stroke, and draws in air on the up stroke through a reverse mounted umbrella valve (63). A third umbrella (64) mounted in the air piston acts as an air relief valve to prevent the chemical bottle from over pressurizing. Air pressure leaves the air cylinder cap (65) via flexible tubing (66) that is attached to a barb on the docking seal mounting (4). Air pressure passes the opened bottle check valve (14), enters the bottle and acts on the surface of the chemical. Chemical rises up the bottle tubing (17), through the opened check valve (15) and into flexible tubing (69) that is connected to a barb (70) mounted into the lever (35). As the knob is shifted to the left or right, a projection (33) of the knob shifts the lever about a pivot (73) causing the chemical to be directed into either the low or high flow rate half of the funnel where it will be mixed with the water stream above it. The lever serves a second purpose by opening an o-ring (74) sealed port (75) in the air cylinder cap and causing air pressure to evacuate the bottle when the knob returns to off. This allows any chemical in the tubing to drain back into the bottle, preventing it from contaminating a different chemical from the next bottle.

Short tubing attached to the low flow rate (left) half of the funnel directs the dilution into a spray bottle, while a long tubing attached to the high flow rate (right) half of the funnel directs the dilution into a mop bucket.

Other objects, features and advantages of the present invention will be apparent to those skilled in the art. While preferred embodiments of the present invention have been illustrated and described, this has been by way of illustration and the invention should not be limited except as required by the scope of the appended claims and their equivalents. 

1. A fluid dispenser, comprising: a diluent fluid inlet; a fluid-driven proportioning air pump in fluid communication with said diluent fluid inlet, said air pump being driven by fluid from said diluent fluid inlet and having an air outlet isolated from said diluent fluid inlet; a fluid container having first and second openings therein, said first opening in fluid communication with said air outlet of said air pump; and wherein said air pump creates air pressure and flow to evacuate said fluid container of fluid through said second opening.
 2. The fluid dispenser as set forth in claim 1, wherein said fluid-driven proportioning air pump further comprises a positive displacement pump that creates translational or rotational motion to drive said air pump.
 3. The fluid dispenser as set forth in claim 1, wherein said fluid-driven proportioning air pump further comprises an axial flow pump that creates translational or rotational motion to drive said air pump.
 4. The fluid dispenser as set forth in claim 1, wherein said fluid-driven proportioning air pump further comprises a centrifugal pump that creates translational or rotational motion to drive said air pump.
 5. The fluid dispenser as set forth in claim 1, further comprising: a mixing chamber, said second opening in of said fluid container in fluid communication with said mixing chamber; and wherein said diluent fluid inlet is in fluid communication with said mixing chamber and wherein fluid from said fluid container travels to said mixing chamber and is therein diluted by diluent fluid from said diluent fluid inlet.
 6. The fluid dispenser as set forth in claim 5, wherein said fluid-driven proportioning air pump further comprises a fluid inlet and a fluid outlet, said diluent fluid inlet being in fluid communication with said air pump fluid inlet; and wherein said mixing chamber is in fluid communication with said air pump fluid outlet and wherein fluid from said diluent fluid inlet travels to said mixing chamber by first passing through said air pump fluid inlet and said air pump fluid outlet.
 7. The fluid dispenser as set forth in claim 1, further comprising: a first metering outlet in fluid communication with said diluent fluid inlet, said first metering outlet allowing diluent fluid from said diluent fluid inlet to flow from said dispenser at a first flow rate; at least a second metering outlet in fluid communication with said diluent fluid inlet, said second metering outlet allowing diluent fluid from said diluent fluid inlet to flow from said dispenser at a second flow rate; and a diverting mechanism operatively connected with said first and second metering outlets and operable to direct flow of diluent fluid through either of said first and second metering outlets.
 8. The fluid dispenser as set forth in claim 7, further comprising: a mixing chamber, said second opening in of said chemical container in fluid communication with said mixing chamber; and wherein said first and second metering outlets are each selectively in fluid communication with said mixing chamber and wherein fluid from said chemical container travels to said mixing chamber and is therein diluted by diluent fluid from said first or second metering outlet.
 9. The fluid dispenser as set forth in claim 7, wherein said fluid-driven proportioning air pump further comprises a fluid inlet and a fluid outlet, said diluent fluid inlet being in fluid communication with said air pump fluid inlet; and wherein said first and second metering outlets are in fluid communication with said air pump fluid outlet and wherein fluid from said diluent fluid inlet travels to said first and second metering outlets by first passing through said air pump fluid inlet and said air pump fluid outlet.
 10. The fluid dispenser as set forth in claim 7, wherein at least one of said first and second metering outlets further comprises a screen and a nozzle.
 11. The fluid dispenser as set forth in claim 7, wherein at least one of said first and second metering outlets further comprises a check valve, the opening and closing of said check valve being controlled by said diverting mechanism.
 12. The fluid dispenser as set forth in claim 7, wherein said diverting mechanism provides for selection of at least three positions including no flow of diluent fluid from either of said first and second metering outlets, flow of diluent fluid from said first metering outlet only, and flow of diluent fluid from said second metering outlet only.
 13. The fluid dispenser as set forth in claim 12, wherein said diverting mechanism further comprises means for maintaining one of said positions once selected.
 14. The fluid dispenser as set forth in claim 12, wherein said diverting mechanism is biased to remain in said no flow of diluent fluid position in the absence of a different selection.
 15. The fluid dispenser as set forth in claim 12, wherein said diverting mechanism further comprises means for holding said diverting mechanism in one of said positions.
 16. The fluid dispenser as set forth in claim 1, further comprising a connection between said air outlet of said proportioning air pump and said fluid container further comprising: a generally vertical wall associated with said dispenser and a generally horizontal support surface connected to said wall; at least one rail mounted to said wall at an angle relative to said support surface; a carriage slideably mounted to said rail; a docking cap mounted within said docking cap; and wherein said docking cap engages a neck of said fluid container as said fluid container is slid across said support surface, resulting in said docking cap and said carriage sliding at a downward angle relative to said support surface along said rail and compressing said docking seal onto a top surface of said fluid container.
 17. The fluid dispenser as set forth in claim 16, wherein said docking cap is mounted for generally vertical movement within said carriage and further comprising a spring associated with said docking cap and said carriage which exerts a downward force on said docking cap relative to said carriage.
 18. The fluid dispenser as set forth in claim 16, wherein said rail comprises a lower end and a higher end and further comprising a spring acting on said carriage as said carriage approaches said lower end of said rail to exert a force on said carriage in a direction toward said higher end of said rail.
 19. The fluid dispenser as set forth in claim 16, wherein said docking cap further comprises an elastomer sealing element that engages said top surface of said fluid container.
 20. The fluid dispenser as set forth in claim 16, wherein said first opening of said fluid container further comprises a first normally-closed check valve and said second opening of said fluid container further comprises a second normally-closed check valve and wherein said docking cap further comprises first and second protrusions to engage and open said first and second check valves when said docking cap engages said top surface of said fluid container.
 21. The fluid dispenser as set forth in claim 1, wherein said second opening of said fluid container further comprises a metering orifice.
 22. A fluid dispenser for use with a fluid container having an air inlet and fluid outlet therein, comprising: a diluent fluid inlet; a fluid-driven proportioning air pump in fluid communication with said diluent fluid inlet, said air pump being driven by fluid from said diluent fluid inlet and having an air outlet isolated from said diluent fluid inlet; a connection between said air outlet of said proportioning air pump and said air inlet of said fluid container; and wherein said proportioning air pump creates air pressure and flow into said fluid resulting in the evacuation of fluid through said fluid outlet of said fluid container.
 23. A fluid dispenser for use with a fluid container, comprising: a diluent fluid inlet; a fluid-driven proportioning air pump in fluid communication with said diluent fluid inlet, said air pump being driven by fluid from said diluent fluid inlet and having an air outlet isolated from said diluent fluid inlet; a connection between said air outlet of said proportioning air pump and said fluid container further comprising; a generally vertical wall associated with said dispenser and a generally horizontal support surface connected to said wall; at least one rail mounted to said wall at an angle relative to said support surface; a carriage slideably mounted to said rail; a docking cap mounting within said docking cap; and wherein said docking cap engages a neck of said fluid container as said fluid container is slid across said support surface, resulting in said docking cap and said carriage sliding at a downward angle relative to said support surface along said rail and compressing said docking cap onto a top surface of said fluid container.
 24. The fluid dispenser as set forth in claim 23, wherein said docking cap is mounted for generally vertical movement within said carriage and further comprising a spring associated with said docking cap and said carriage which exerts a downward force on said docking cap relative to said carriage.
 25. The fluid dispenser as set forth in claim 23, wherein said rail comprises a lower end and a higher end and further comprising a spring acting on said carriage as said carriage approaches said lower end of said rail to exert a force on said carriage in a direction toward said higher end of said rail.
 26. The fluid dispenser as set forth in claim 23, wherein said docking cap further comprises an elastomer sealing element that engages said top surface of said fluid container.
 27. The fluid dispenser as set forth in claim 23, wherein said first opening of said fluid container further comprises a first normally-closed check valve and said second opening of said fluid container further comprises a second normally-closed check valve and wherein said docking cap further comprises first and second protrusions to engage and open said first and second check valves when said docking cap engages said top surface of said fluid container.
 28. A fluid dispenser, comprising: a diluent fluid inlet; a mixing chamber; a fluid-driven proportioning air pump in fluid communication with said diluent fluid inlet, said air pump being driven by fluid from said diluent fluid inlet and having an air outlet isolated from said diluent fluid inlet; a fluid container having first and second openings therein, said first opening in fluid communication with said air outlet of said air pump, said second opening in fluid communication with said mixing chamber; and wherein said diluent fluid inlet is also in fluid communication with said mixing chamber and wherein fluid from said fluid container travels to said mixing chamber is therein diluted by fluid from said diluent fluid inlet.
 29. A fluid dispenser, comprising: a diluent fluid inlet; a mixing chamber; a fluid-driven proportioning air pump in fluid communication with said diluent fluid inlet, said air pump being driven by fluid from said diluent fluid inlet and having an air outlet isolated from said diluent fluid inlet; a fluid container having first and second openings therein, said first opening in fluid communication with said air outlet of said air pump, said second opening in fluid communication with said mixing chamber; a connection between said air outlet of said proportioning air pump and said first opening of said fluid container further comprising; a generally vertical wall associated with said dispenser and a generally horizontal support surface connected to said wall; at least one rail mounted to said wall at an angle relative to said support surface; a carriage slideably mounted to said rail; a docking cap mounting within said docking cap; and wherein said docking cap engages a neck of said fluid container as said fluid container is slid across said support surface, resulting in said docking cap and said carriage sliding at a downward angle relative to said support surface along said rail and compressing said docking cap onto a top surface of said fluid container; and wherein said diluent fluid inlet is also in fluid communication with said mixing chamber and wherein fluid from said fluid container travels to said mixing chamber and is therein diluted by fluid from said diluent fluid inlet.
 30. A method of evacuating fluid from a fluid container, comprising the steps of: providing a fluid-driven proportioning air pump having a fluid inlet, a fluid outlet, and an air outlet; supplying a diluent fluid to said proportioning air pump through said fluid inlet of said air pump; delivering a volume of pressurized air from said air outlet of said air pump to an interior of said fluid container through a first opening in said fluid container in order to displace a similar volume of fluid from said container and evacuate said volume of fluid from said container through a second opening in said container; and diluting said volume of fluid displaced from said container with diluent fluid from said fluid outlet of said air pump.
 31. The method of evacuating fluid as set forth in claim 30, wherein said step of diluting said volume of fluid further comprises the steps of: delivering said volume of fluid displaced from said container to a mixing chamber; and delivering diluent fluid from said fluid outlet of said air pump to said mixing chamber.
 32. The method of evacuating fluid as set forth in claim 31, wherein said step of delivering diluent fluid to said mixing chamber further comprises the step of routing said diluent fluid through a metering outlet before said diluent fluid reaches said mixing chamber.
 33. The method evacuating fluid as set forth in claim 31, wherein said step of delivering diluent fluid to said mixing chamber further comprises the steps of: selecting one of at least first and second metering outlets, each of said at least first and second metering outlets providing a different flow rate; and routing said diluent fluid through said selected metering outlet before said diluent fluid reaches said mixing chamber. 